i got a file from an app inventor teacher today.
he use the txtbox to replace my slider for entering the RGB number.
And he set the original color-list to an empty list rather than my (0,0,0).
So the app can run perfectly for sending text and change the screen color.
The aia file is just as attach
Then i fix my app by saving the slider data into text first and transfer via bluetooth with CSV row method.
It's seen that if i just sending the list of three texts, the function will alright.
But i still cannot understand why this will happen.